Supercooling and nucleation: Difference between revisions

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'''Supercooling''', undercooling and nucleation.
'''Supercooling''', undercooling and nucleation.
==Volmer and Weber kinetic model==  
==Volmer and Weber kinetic model==  
Volmer and Weber kinetic model <ref>M. Volmer and A. Weber "Keimbildung in übersättigten Gebilden", Zeitschrift für Physikalische Chemie '''119''' pp. 277-301 (1926)</ref>:
Volmer and Weber kinetic model <ref>M. Volmer and A. Weber "Keimbildung in übersättigten Gebilden", Zeitschrift für Physikalische Chemie '''119''' pp. 277-301 (1926)</ref> results in the following nucleation rate:


:<math>\label{eq_IVW}I^{VW} = N^{eq}(n^*) k^+(n^*) =  k^+(n^*) N_A \exp \left( -\frac{W(n^*)}{k_BT}  \right)</math>
:<math>I^{VW} = N^{eq}(n^*) k^+(n^*) =  k^+(n^*) N_A \exp \left( -\frac{W(n^*)}{k_BT}  \right) \label{eq_IVW} </math>
==Szilard nucleation model==
==Szilard nucleation model==
==Homogeneous nucleation temperature==
==Homogeneous nucleation temperature==
The homogeneous nucleation temperature (<math>T_H</math>) is the [[temperature]] below which it is almost impossible to avoid spontaneous and rapid freezing.
The homogeneous nucleation temperature (<math>T_H</math>) is the [[temperature]] below which it is almost impossible to avoid spontaneous and rapid freezing.
==Zeldovich factor==
==Zeldovich factor==
The Zeldovich factor, <math>Z</math>, modifies the Volmer and Weber expression \eqref{eq_IVW}, making it applicable to spherical clusters:
The Zeldovich factor <ref>J. B. Zeldovich "On the theory of new phase formation, cavitation", Acta Physicochimica URSS '''18''' pp. 1-22 (1943)</ref> (<math>Z</math>) modifies the Volmer and Weber expression \eqref{eq_IVW}, making it applicable to spherical clusters:


:<math>Z= \sqrt{\frac{ \vert \Delta \mu \vert }{6 \pi k_B T n^*}} </math>
:<math>Z= \sqrt{\frac{ \vert \Delta \mu \vert }{6 \pi k_B T n^*}} </math>
==Zeldovich-Frenkel equation==
Zeldovich-Frenkel [[master equation]] is given by
:<math>\frac{\partial N(n, t)}{\partial t} =  \frac{\partial }{\partial n}  \left( k^+  (n) N^{eq} (n) \frac{\partial }{\partial n}  \left( \frac{N(n, t)}{N^{eq}(n)} \right)  \right)</math>
==See also==
==See also==
*[[Glass transition]]
*[[Glass transition]]
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<references/>
<references/>
;Related reading
;Related reading
*[http://dx.doi.org/10.1063/1.1750413 J. Frenkel "Statistical Theory of Condensation Phenomena", Journal of Chemical Physics '''7''' pp. 200-201 (1939)]
*[http://dx.doi.org/10.1063/1.2779036 Lawrence S. Bartell and David T. Wu "Do supercooled liquids freeze by spinodal decomposition?", Journal of Chemical Physics '''127''' 174507 (2007)]
*[http://dx.doi.org/10.1063/1.2779036 Lawrence S. Bartell and David T. Wu "Do supercooled liquids freeze by spinodal decomposition?", Journal of Chemical Physics '''127''' 174507 (2007)]
*[http://dx.doi.org/10.1063/1.471721 Pieter Rein ten Wolde, Maria J. Ruiz-Montero and Daan Frenkel "Numerical calculation of the rate of crystal nucleation in a Lennard-Jones system at moderate undercooling", Journal of Chemical Physics '''104''' pp. 9932-9947 (1996)]
*[http://dx.doi.org/10.1063/1.471721 Pieter Rein ten Wolde, Maria J. Ruiz-Montero and Daan Frenkel "Numerical calculation of the rate of crystal nucleation in a Lennard-Jones system at moderate undercooling", Journal of Chemical Physics '''104''' pp. 9932-9947 (1996)]

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Supercooling, undercooling and nucleation.

Volmer and Weber kinetic model

Volmer and Weber kinetic model [1] results in the following nucleation rate:

Failed to parse (unknown function "\label"): {\displaystyle I^{VW} = N^{eq}(n^*) k^+(n^*) = k^+(n^*) N_A \exp \left( -\frac{W(n^*)}{k_BT} \right) \label{eq_IVW} }

Szilard nucleation model

Homogeneous nucleation temperature

The homogeneous nucleation temperature () is the temperature below which it is almost impossible to avoid spontaneous and rapid freezing.

Zeldovich factor

The Zeldovich factor [2] () modifies the Volmer and Weber expression \eqref{eq_IVW}, making it applicable to spherical clusters:

Zeldovich-Frenkel equation

Zeldovich-Frenkel master equation is given by

See also

References

  1. M. Volmer and A. Weber "Keimbildung in übersättigten Gebilden", Zeitschrift für Physikalische Chemie 119 pp. 277-301 (1926)
  2. J. B. Zeldovich "On the theory of new phase formation, cavitation", Acta Physicochimica URSS 18 pp. 1-22 (1943)
Related reading
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